1. Field of the Invention
The invention relates to security enclusures or products such as money safes and the like having body wall and door construction providing barriers resistant to forced entry attack by cutting torches, power drills, impact hammers, abrasive cutting wheels, power saws, carbide drills, and other tools or pressure applying devices.
More particularly the invention relates to providing money safes and the like with metal encased homogeneous monolithic fractured aggregate and metal fiber reinforced concrete body and door walls.
Further, the invention relates to providing a new forced entry attack resistant money safe body and door wall construction and especially new methods of manufacture of such safe walls to replace prior safe body and door walls having layers of torch and tool resistant plates in the cavities of the safe body and door walls heretofore used to meet Underwriters' requirements for such products.
2. Description of the Prior Art
Traditionally, safe body and door walls have been built with the desired thickness to obtain the degree of security required. Such walls essentially are solid slabs formed of joined together layers of various metals, alloys or materials required to resist the various attack measures which might be used directly on the walls in an attempt to gain access to the interior of the safe. An example of such multi-plate wall security construction is shown in this Assignee's previous Graber U.S. Pat. No. 3,110,271.
Underwriters' Specifications classify a safe wall as failing to be burglary resistant if a 2 square inch opening may be formed through the wall by 30 man-minutes of working time of the attacker or attackers.
Multi-plate security walls for security safe body and door walls of the type shown in said U.S. Pat. No. 3,110,271 are difficult and expensive to manufacture. Such multi-plate construction has security weakness in areas or zones, particularly corner zones and where plate seams, splices or joints are required. These weak zones do not have the same level of protection as the main multi-plate body. Such weak zones are known to intruder and frequently are locations of attack.
For many years efforts have been exerted in the field of security products to find an alternate form of protection that would be less expensive and easier to build than the traditional multi-plate protection, and which would provide at least equivalent security characteristics against all known type and means of attack.
Developments in the field of metal fiber reinforced concrete were examined and explored, such as the concrete overlay construction of U.S. Pat. No. 4,339,289, and metal fiber reinforced refractory concrete shapes used in the steel industry for plunging bells, injection lances or pier blocks of U.S. Pat. No. 4,366,255.
However, such improved prior metal fiber reinforced concrete overlay and refractory products and procedures for their manufacture are not adapted to be used, as such, to provide safe wall security barriers with the required degree of attack resistance against the formation of attack openings through safe body and door walls, and having security characteristics at least equivalent to said traditional multi-plate protection.
Further, we have discovered that metal fiber reinforced safe wall security barriers should contain a combination of relatively high percentages by volume of both metal fibers and relatively large sized ceramic aggregate phases as the concrete phase reinforcement to achieve such required degree of attack resistance at least the equivalent to that provided by said traditional multi-plate protection.
It was found difficult if not impossible, to mix such high fiber-aggregate content reinforced concrete formulation in a typical concrete mixer and to introduce the same into the body and door wall cavities of a safe.
These difficulties relate primarily to the special configurations of the cavities in safe body and door walls in which the high fiber-aggregate content reinforced concrete formulation is to be cast; to the necessity of positioning copper plates at particular locations or zones in the safe wall cavities; to the fact that the barriers, including copper plates, must be cast and completely encased in wall cavities formed by metal shell walls that ultimately form the metal encasement for the barriers; and to the necessity of providing an access opening initially in the shell walls through which the cavities are filled and to then closing such access openings.
For example, the safe body cavity formed by metal encasing shell walls has five cavity portions, namely, two side wall cavity portions, a back wall cavity portion and top and bottom cavity wall portions. Further, these cavity portions are connected together and the protective barrier formed in the connected cavity portions should be a homogeneous monolithic substructure free of zones of weakness, such as zones of weakness heretofore present in the described multi-plate protective prior art safe walls.
Also, different manners of handling the safe body and door walls are used in forming the barrier in the five sided safe body component on the one hand, and in forming the barrier in the substantially rectangular flat door component on the other hand. Also, the positioning of copper plate elements in the body and door cavities require different procedures.
Further, different procedures must be used for completing the metal encasement of the cast barrier in the body on the one hand, and for completing the metal encasement of the cast barrier in the door on the other hand.
Although some prior art concrete security wall structures have been proposed for safes, such as described in U.S. Pat. No. 4,377,977, such prior structures apparently do not have attack resistant characteristics like those provided by the new reinforced concrete wall structure for the body and door components of a money safe of the invention wherein copper members become an integral part of or cooperate with the new fiber and aggregate reinforced concrete structure.
Accordingly, there has existed in the art a long-standing need for a barrier construction effective to resist burglary attack upon safe body and door walls, which would be less expensive than, and have at least equivalent attack resistance characteristics to those of the traditional multi-plate security protective safe body and door wall constructions of the prior art.
The new high fiber-aggregate content reinforced concrete formulation of the present invention, and the discoveries of new procedures by which such reinforced concrete formulation may be cast in safe body and door walls to avoid or satisfy the difficulties described, provide answers to said long-standing need that has existed in the art.